1. Field of the Invention
The invention relates to a circuit arrangement for controlling/regulating photovoltaic systems that comprise a plurality of solar generators connected in series and/or in parallel.
2. Description of Related Art
It is generally known that photovoltaic solar generators perform optimally only if the generator is operated at a specific operating point, i.e., the maximum power point, which is referred to as MPP in the following. With each generator, the MPP depends on the respective external operating conditions, in particular the current radiation intensity and the temperature as well as the condition of the generator itself, in particular as a condition of production tolerances, age, defects, contaminations, etc. For these reasons, each generator has a specific MPP current IMPP and/or a specific MPP voltage UMPP.
It is furthermore generally known that in photovoltaic systems, solar generators are connected in series to so-called strings so as to obtain specific output voltages. Depending on the desired output power, an appropriate number of strings are connected in parallel. The serial connection causes the current flowing through all of the solar generators of a string to be of the same strength. However, differences in the MPP currents of the individual solar generators of a string lead to a loss of performance of the photovoltaic system because not every solar generator can be operated in its optimal operating range.
The object to be attained by the invention is to reduce performance losses of solar generators connected in series and/or parallel.